Cocaine-exposed children are at high risk for iron deficiency (anemic and non-anemic) due to associated biological and maternal risk factors. Studies have reported that both cocaine exposure and iron deficiency during prenatal and early infancy periods have independent effects on neurotransmitter (dopamine) regulation. Despite this common link, there have been no studies to date that have explored the association of iron deficiency and developmental deficit in cocaine-exposed children. In order to test this hypothesis hematology data will be collected for children at age 2 years, who have been recruited to a major ongoing prospective study of the effects of cocaine exposure and other risk factors on early child development. Preliminary examination (using hemoglobin and hematocrit) of 32 children from this cohort indicates a high prevalence of anemia. Given attrition rates from the primary study and our anticipated participation rate for blood collection, we expect to have a sample of 268 two-year old children (approximately equal proportions of exposed and non-exposed) to achieve the aims of the study. These aims are (1) To determine the prevalence of iron deficiency in cocaine-exposed vs. non-exposed children; (2) To assess the interaction effect of iron deficiency and maternal cocaine exposure on the neurodevelopment of the children; (3) To determine the effect of all risk factors and their interaction on the neurodevelopment of children. Approximately, 90 percent of the sample is African-American and over 75 percent belongs to SES class V. Data collection will include hematology measures such as hemoglobin, hematocrit, mean corpuscular volume, ferritin, percent transferrin saturation, lead and seropositivity to a parasitic infection (toxocara canis), as well as two questionnaires on pet ownership and pica. Other data required will be provided by the primary study and includes: Bayley Scales of Infant Development (MDI, PDI and IBR), substance abuse assessments, maternal and infant measures, maternal IQ, HOME Scale, and socio-demographic variables. Statistical analyses will consist primarily of multivariate analyses and risk ratios adjusted for the effects of confounding. The proposed cross-sectional study will determine the feasibility of conducting longitudinal and intervention studies. Our findings are expected to guide clinicians regarding the identification and treatment of iron deficiency.